This invention is concerned with connection of oxygen and other gas lines, and, more particularly, to a quick-disconnect fitting for allowing oxygen lines or other gas lines to be quickly connected or disconnected.
In hospitals and clinics as well as emergency medical vehicles, and also on non-institutional premises, where an oxygen line must be connected to a source of oxygen under pressure for supplying medical oxygen to a patient, whether for emergency usage or routine clinical usage or treatment, it is extremely important to facilitate the quick connection and disconnection of an oxygen line, while ensuring that the oxygen line cannot be plugged into an improper source, such as a compressed air line or another pressurized gas source. A fitting for gas line connection and disconnection should provide for safety of connection, ensuring a positive, leak-free connection which will preclude leakage of oxygen, since pressurized oxygen supports rapid combustion and even conduces to explosive gas accumulation, and thus must not be permitted to be vented into the surrounding atmosphere. Such fitting, however, must ensure that when the oxygen line is disconnected, the pressurized oxygen will not be permitted to leak from the fitting.
Accordingly, among the several objects of the invention may be noted the provision of an improved quick-disconnect fitting for connection and disconnection of a gas line; the provision of such a fitting which is especially useful for connection and disconnection of oxygen lines such as for supplying medical oxygen under pressure for patient usage; the provision of such a fitting which provides a secure seal against leakage of the gas from a source of same when the gas line is disconnected; and which is configured for permitting connection of a gas line only to a pre-determined gas source; the provision of such a fitting which although quite economical to manufacture, is long lasting and reliable in operation, and ensures against leakage even in the event of breakage of the fitting; and the provision of such a fitting which is very compactly configured.
It is also an object of the present invention to provide such an improved quick-disconnect fitting which utilizes a cap defining a receptacle for a gas line plug, wherein the cap is of synthetic resin material and is so attached to a valve body of the fitting as to eliminate or minimize stress within the cap such as has heretofore caused stress failure of synthetic parts in prior art constructions, it being also an object of the invention to provide such a cap which is threadless whereby there are no stresses associated with threads either during their manufacture or use for securement. A further object of the invention is the provision of such a fitting in which the cap provides only mechanical securement of elements for securement and disconnection of the plug, while all gas pressure-receiving elements are contained entirely within the valve body, which is most preferably of metal.
An additional object of the invention is the provision of such a fitting which allows venting of overpressure conditions including pressure relief operation of fail-safe type in the event of extreme pressure buildup in a gas line supplying gas under pressure to the fitting.
Briefly, a quick-disconnect of the invention as useful for connecting an oxygen line, for example, either to a source of oxygen under pressure, as well as for quickly disconnecting the line, includes a valve body which is threaded at its inner end for being threadably received by the oxygen source, such as a gas manifold. The valve body includes a plunger-type valve axially shiftable between open and closed positions, and carrying at its inner end a seal for sealing engagement with the valve body when closed. A compression spring surrounding the valve urges it into closed position. A cap molded of synthetic resin material is carried at the outer end of the valve body, being provided with a receptacle for receiving an oxygen line plug of the type having a plug flange. The cap includes a locking plate which is shiftable transversely to the receptacle and is configured for locking engagement with the plug flange. The plug includes a nose for engaging and maintaining open the valve member so long as the plug is retained by the cap in locked engagement. The cap receptacle is cross-sectionally configured for unique mutual engagement of the plug to prevent improper connection thereof.